Разработка алгоритмического и программного обеспечения для укладки графов на плоскости

Объектом исследования является процесс укладки графов на плоскость. Цель работы - Разработка алгоритмического и программного обеспечения для укладки графов на плоскости. В процессе работы производилось изучение существующих способов отображения планарных и непланарных графов на плоскости и разработка программного обеспечения для отображения диаграмм баз данных на плоскости.The object of the study is the process of laying graphs on a plane. The aim of the work is to Develop algorithmic and software for laying graphs on the plane. In the course of work, the study of existing methods of displaying planar and non-planar graphs on the plane and the development of software for displaying database digrams on the plane were carried out

Growth condition dependence of unintentional oxygen incorporation in epitaxial GaN

Growth conditions have a tremendous impact on the unintentional background impurity concentration in gallium nitride (GaN) synthesized by molecular beam epitaxy and its resulting chemical and physical properties. In particular for oxygen identified as the dominant background impurity we demonstrate that under optimized growth stoichiometry the growth temperature is the key parameter to control its incorporation and that an increase by 55 °C leads to an oxygen reduction by one order of magnitude. Quantitatively this reduction and the resulting optical and electrical properties are analyzed by secondary ion mass spectroscopy, photoluminescence, capacitance versus voltage measurements, low temperature magneto-transport and parasitic current paths in lateral transistor test structures based on two-dimensional electron gases. At a growth temperature of 665 °C the residual charge carrier concentration is decreased to below 1015 cm−3, resulting in insulating behavior and thus making the material suitable for beyond state-of-the-art device applications

Optical coherence tomography (OCT) angiography findings in retinal arterial macroaneurysms

Background Optical coherence tomography angiography is a novel imaging technique that allows dyeless in vivo visualization of the retinal and choroidal vasculature. The purpose of this study was to describe optical coherence tomography (OCT) angiography findings in patients with retinal arterial macroaneurysms (RAMs). Methods Three eyes of three patients with RAMs were retrospectively included. Fundus photography, OCT, fluorescein angiography (FA), and OCT angiography were performed. The entire imaging data was analyzed in detail. Results OCT angiography could detect the RAMs noninvasively without dye injection. By simultaneously observing the OCT scans, it was possible to determine the depth of the RAMs in the retina, to detect the exact localization in relation to the main vessel, and to determine the level of blood flow in the RAMs. Conclusions OCT angiography can clearly visualize RAMs without use of a dye. It also allows layer-specific observation of blood flow in each layer of the RAM. OCT angiography provides additional dynamic information on RAMs, which is not obtained with FA and facilitates a better understanding of its morphology and activity. This information in combination with ICG and fluorescein angiography can help to optimize direct laser treatment

Pro-resolving lipid mediator Resolvin D1 serves as a marker of lung disease in cystic fibrosis.

BACKGROUND:Cystic fibrosis (CF) is an autosomal recessive genetic disorder that affects multiple organs, including the lungs, pancreas, liver and intestine. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) locus lead to defective proteins and reduced Cl- secretion and Na+ hyperabsorption in the affected organs. In addition, patients suffering from CF display chronic inflammation that contributes to the pathogenesis of CF. Recent work suggests that CF patients have a reduced capacity to biosynthesize specialized pro-resolving lipid mediators (SPMs), which contributes to the development and duration of the unwanted inflammation. Alterations in the metabolism of arachidonic acid (AA) and docosahexaenoic acid (DHA) to specialized pro-resolving mediators (SPMs), like lipoxins (LXs), maresins (MaRs), protectins (PDs) and resolvins (Rvs), may play a major role on clinical impact of airway inflammation in CF. METHODS:In this study, our aims were to detect and quantitate Resolvin D1 (RvD1) in sputum and plasma from patients with CF and compare levels of RvD1 with biomarkers of inflammation and lung function. We studied 27 CF patients aged 6 to 55 years (median 16 years) in a prospective approach. RESULTS:DHA can be found in the plasma of our CF patients in the milligram range and is decreased in comparison to a healthy control group. The DHA-derived pro-resolving mediator Resolvin D1 (RvD1) was also present in the plasma (286.4 ± 50 pg/ mL, mean ± SEM) and sputum (30.0 ± 2.6 pg/ mL, mean ± SEM) samples from our patients with CF and showed a positive correlation with sputum inflammatory markers. The plasma concentrations of RvD1 were ten times higher than sputum concentrations. Interestingly, sputum RvD1/ IL-8 levels showed a positive correlation with FEV1 (rs = 0.3962, p< 0.05). CONCLUSIONS:SPMs, like RvD1, are well known to down-regulate inflammatory pathways. Our study shows that the bioactive lipid mediator RvD1, derived from DHA, was present in sputum and plasma of CF patients and may serve as a representative peripheral biomarker of the lung resolution program for CF patients

Repeatability, reproducibility and agreement of foveal avascular zone measurements using three different optical coherence tomography angiography devices.

PURPOSE:To evaluate the repeatability, the reproducibility and the agreement of foveal avascular zone (FAZ) measurements using three different optical coherence tomography angiography (OCT-A) devices. PROCEDURES:This prospective study included 24 eyes of 24 healthy volunteers. OCT-A imaging was performed using RTVue XR Avanti, Canon OCT-HS100 and Spectralis OCT-A. Repeated measurements were performed under the same conditions on two separate days, and the area of the FAZ was determined and analyzed using the above devices. RESULTS:All three devices showed a high ICC and there was no significant difference between the ICCs (pairwise comparison) of the three devices (Optovue-Canon (p = 0.66); Canon-Heidelberg (p = 0.21); Heidelberg-Optovue (p = 0.37). Agreement analysis of the three devices revealed a significant elevation of FAZ area values with the Heidelberg device and a slight underestimation of the FAZ area with the Canon device. Nevertheless, overall we found a high level of agreement between all of the three devices (ICC ≥ 0.958 (0.905-0.982)). CONCLUSIONS:Good reproducibility and repeatability were observed for all three devices. However, the agreement analysis revealed slight, but significant differences, which might limit alternating use of these devices for clinical research and follow-up examinations

Non-perturbative four-wave mixing in InSb with intense off-resonant multi-THz pulses

High-field multi-THz pulses are employed to analyze the coherent nonlinear response of the narrow-gap semiconductor InSb which is driven off-resonantly. Field-resolved four-wave mixing signals manifest the onset of a non-perturbative regime of Rabi flopping at external amplitudes above 5 MV/cm per pulse. Simulations based on a two-level quantum system confirm these experimental results.publishe